In recent years, in wireless communication systems such as mobile phone systems, in order to further increase the speed, bandwidth, and so forth of wireless communication, a next-generation wireless communication technology has been discussed. For example, in 3GPP (3rd Generation Partnership Project) serving as a standardization body, a communication standard called LTE (Long Term Evolution) and a communication standard based on the wireless communication technology of LTE and called LTE-A (LTE-Advanced) have been proposed.
In such a wireless communication system, a technique for realizing reduction of power consumption of the entire system has been proposed. In this technique, for example, traffic amounts in the coverage areas of a plurality of base stations are measured by a control station, the transmission power levels of the base stations are decreased or increased or ON/OFF of power supplies thereof is performed in accordance with the traffic amounts or statistical changes in the traffic amounts, and thus, power consumption of the entire system is reduced.